A contemporary cloud based datacenter can make applications, services and data available to very large numbers of client computers simultaneously. For example, a given node in the datacenter can have millions of concurrent network connections. Clusters are groups of computers that can be deployed in these and other contexts to provide high availability. Clusters use groups of redundant computing resources in order to provide continued service when individual system components fail. Clusters eliminate single points of failure by providing multiple servers, multiple network connections, redundant data storage, etc. Clustering systems are often combined with storage management products that provide additional useful features, such as journaling file systems, logical volume management, etc.
A client may periodically poll one or more servers in a datacenter to request software updates, configuration settings, log events, policy updates, and/or various other types of data. A request body may comprise data to be utilized by the server for producing the response, for example, the client hardware and/or software configuration needed for selecting the required software updates, or other client registration or context information used by the server to configure a response to a client polling request.
As contemporary web applications can serve hundreds of millions of clients, the amount of network traffic between the clients and the servers can be considerable.